OK,

Wired my dme into my 914 harness.

Symptom, engine won't turn off with key starts and runs fine.

Source: Two of the three black wires in my 1986 3.2 are tied into one large black wire from 914 tunnel. Thought this was the right way to do this...

the other little black wire from the dme is for the tach upshift light (not used on my car)

Any thoughts?

get a PMS adapter harness ...
Andy

so what I need is to find a "run" wire, one that is only hot when the car is running

Using a voltmeter, it should be easy to find a fuse that only has +12V with the key on, yet has 0V when the key is off. Typically, the radio was wired like that. Also the brake lights only work with the key on.

Normally in porsche wiring harnesses, it is customary for red wires to be always hot, while black wires are switched hots.

Since you switched ignition switches, I am at a loss as to how yours works. Perhaps study a wiring schematic for whatever yours came from, or use the voltmeter approach.

check to make sure the "black" wire you tied into is actually hot (+12v) at all times as I suspect.

It's only wiring, so it is a simple thing. It can sometimes be tricky to troubleshoot until you understand it.

If I was at home, I could look up some things, but I am out at a jobsite. I should be home late Tuesday, but we are going to the town Fireworks when I get home.

I still say, find a fuse that is only hot (+12v) with the key on and use that to power the black wires for the DME.

P.S. Don't listen to Andy, he didn't do his own. Besides, PMS sucks out loud!!!!!

Indeed.

Take a pic of the wiring around the DME and then tell me what yr 3.2.

Have you found a +12v source that is only hot with the ignition switch in the "on" position?

Where are you at with this?

What year 911/914-6 ignition switch did you use?

Did you use the standard color codes when you switched ignition switches?

On a 914-6 ignition switch, you should have the following terminals:

#30 +12v (direct from battery) input
#57 +12v (feed to turn signal switch) unswitched ?????
#15 +12v (output to various circuits) Black (hot in run and start)
#50 +12v (feed to starter solenoid) Yellow (hot in start position only)
#X +12V (output to various circuits) Red (interupted while in start position)


You want your black wires (for the DME) to be fed by terminal 15 on your ignition switch.

I hope this is helpful.

fixed.

ran new wire from run circuit off ignition to brain. Nice to fix all wiring bugs before installing carpet...